Ce que l imagerie nanoscopique des synapses nous apprend sur le fonctionnement du cerveau

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3 Daniel Choquet I2N Conférence Ce que l imagerie nanoscopique des synapses nous apprend sur le fonctionnement du cerveau D. Choquet Institut Interdisciplinaire de Neurosciences, CNRS UMR 5297, Université Bordeaux 2, Talence, France Les récepteurs de neurotransmetteurs sont concentrés dans des domaines membranaires spécialisés, les synapses. Le nombre de récepteurs au niveau des synapses détermine l'efficacité de la transmission synaptique, un paramètre déterminant des mécanismes de mémoire et d'apprentissage. La connaissance des mécanismes de contrôle du trafic des récepteur vers et hors des synapses est donc de première importance, d'autant plus que ces processus sont susceptibles d'être à la base de nombreuses pathologies tels que les maladies neurodégénératives ou psychiatriques. Au cours des dernières années, les connaissances sur le rôle et les propriétés d organisation nanoscopique et de diffusion des récepteurs a fait un pas en avant important grâce au développement des techniques de détection et de suivi de molécule uniques et les approches de super-résolution. Toutefois, la sous-distribution des récepteurs dans des sous-domaines dans les neurones vivants, ainsi que la dynamique des récepteurs dans ces sous-domaines reste mal connue. Nous présenterons l'application de ces approches à l'étude du trafic des récepteurs du glutamate de type AMPA et sa régulation par l'activité neuronale.

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7 Hugo Barès NEO CO-1 Production et fonctionnalisation de graphène en solution via la réaction de Diels-Alder H. Barès, a S. Bonhommeau, a J.-B. Verlhac, a D. Bassani a a Institut des Sciences Moléculaires, CNRS UMR 5255 Université de Bordeaux, 351, Cours de la Libération, Talence, France Depuis la découverte des propriétés physiques et électroniques du graphène en 2004, (1) un très grand nombre de travaux ont été réalisés afin de produire et modifier ce nouveau matériau du futur dans le but d étendre et améliorer ses capacités et ses applications. D un point de vue chimique, le graphène présente la particularité structurale d exister à la fois sous forme de diène et de diénophile, en raison d un gap nul. Dans la réaction de cycladdition [4+2], le graphène peut ainsi réagir avec des diénophiles ou des diènes activés, tels que le 9- méthylanthracène. (2) Nous avons développé au laboratoire un procédé permettant l exfoliation chimiquement assistée du graphite en solution, basé sur une réaction de cycloaddition réversible. (3) Cette approche repose sur la réaction de Diels-Alder, entre le graphite et un diène masqué très réactif, l anthrone, (4) assistée par une légère sonication. Cela se révèle être très efficace dans des solvants organiques volatils qui sont inefficaces pour l exfoliation directe du graphite. En effet, la présence de centres sp 3 et de l adduit sur le squelette carboné du graphène permet la séparation et la solubilisation des feuillets de graphène. L intérêt de cette méthode est qu ici le graphène en solution est un adduit de cycloaddition, et il peut alors subir la réaction inverse, dite de rétro Diels-Alder. Ainsi, les feuillets de graphène fonctionnalisés retrouvent leur structure π-conjuguée par simple chauffage. Aussi, la présence de groupements fonctionnels sur le diène permet de post-fonctionnaliser les feuillets de graphène et ainsi apporter une plus-value au futur matériau. (1) K. S. Novoselov, A. K. Geim, S. V. Morozov, D. Jiang, Y. Zhang, S. V. Dubonos, I. V. Grigorieva, A. A Firsov. Science, 2004, 306, 666. (2) S. Sarkar, E. Bekyarova, S. Niyogi, R. C. Haddon. J. Am. Chem. Soc. 2011, 133, (3) D. Bassani, J.-B. Verlhac, H. Barès, Patent WO (A3), (4) M. Koerner, B. Rickborn. J. Org. Chem. 1989, 54, 9.

8 Meriem Bouriga GSM/NEO CO-2 Modification of space-charge embedded glass surfaces by photoactive molecules M. Bouriga, V. Rodriguez, N. McClenaghan, M. Dussauze, L. Vellutini, F. Adamietz and T. Buffeteau Bordeaux University, Molecular Sciences Institut (ISM), 351 Cours de la Libération 33405, Talence, France The aim of this project is to modify glass surfaces to give them the potential to host photoactive molecules and to study the optical properties of the resulting novel materials. In this context the glasses were subjected to a thermal polarization technique which embeds charge in the material. The optimization of the poling atmosphere and the electrode type permits the control of the physicochemical properties of the interface by two combined actions: a) chemical activation of the surface to enable the functionalization, and b) introduction of an enhanced internal electric field. In parallel, a grafting protocol harnessing an efficient click reaction, has been established to covalently bind photoactive molecules to a grafted precursor on the glass surface. The chosen fluorescent molecules can have several functions; such as photoswitches, molecular probes and push-pull type molecules. Finally, to characterize the electronic properties and the arrangement of the molecular photoactive assemblies in contact with the space charge embedded substrate, a range of complementary techniques: UV-Visible Reflection Absorption Spectroscopy (UV-Vis RAS), Polarisation Modulation-InfraRed Reflection Absorption Spectroscopy (PM-IRRAS) and second harmonic generation microscopy are employed. This Ph.D. thesis is part of the project Integrated Photonic Architecture which is in the framework of the LabEx Laser and Photonics in Aquitaine LAPHIA. (1) T. Cremoux, M. Dussauze, E. Fargin, T. Cardinal, D. Talaga, F. Adamietz and V. Rodriguez. J. Phys. Chem. C, 2014, 118 (7), (2) S-Y. Ku, K-T. Wong and A. J. Bard. J. Am. Chem. Soc, 2008, 130,

9 Eduardo Cueto Diaz PHOENICS CO-3 Tandem triad systems based on fret for two-photon induced release of glutamate Eduardo Cueto Diaz, 1 Sébastien Picard, 1 Emilie Genin, 1 Guillaume Clermont, 1 Francine Acher, 2 David Ogden, *3 Mireille Blanchard-Desce *1 1 Univ. Bordeaux, Institut des Sciences Moléculaires, CNRS UMR 5255, Talence, France 2 CNRS UMR8601, Université Paris Descartes, Sorbonne Paris Cité, 45 rue des Saint-Pères, Paris cedex, France 3 CNRS UMR8118, Université Paris Descartes, Sorbonne Paris Cité, 45 rue des Saint-Pères, Paris cedex, France Photoactivation of caged compounds under light irradiation, providing an intrisic spatial and temporal control, has emerged as a fascinating tool for many applications especially in the fast developing field of neuroscience (i.e uncaging of neurotransmitters such as L-glutamate) [1]. Among photolabile protecting groups (PPG), the 7-nitroindolinyl (NI) caging moiety has been one the most widely applied in neuroscience because of its remarkable properties including its fast photorelease kinetics and its excellent dark stability. Its use for two-photon (2P) photolysis in the biological spectral window (NIR) offers new perspectives thanks to the improved penetration depth it provides [2] but it remains strongly limited due to the relatively low 2P uncaging sensitivity of the NI group, as is the case for most classical cages. It has created a strong motivation for the development of novel efficient 2P cages. The most traveled routes based on the structural variation of the PPG can lead to disappointing results because such variations that are meant to increase 2P absorption cross-sections in the NIR region may also strongly affect the photochemical properties and result in a decrease of the uncaging quantum yield. In this context, we recently focused on an alternative approach where an optimized 2P absorber acts as an intramolecular sensitizer and transfers its excitation energy to the grafted NI unit in order to preserve its key chemical and photochemical characteristics. We developed the first symmetrical tandem systems composed of two NI-caged glutamate moieties attached to an hydrophilic quadrupolar 2P absorbing module enabling the efficient release of two glutamate molecules per chromophore upon 2P photoactivation in the red-nir range [3]. We demonstrated that this strategy indeed leads to a 10-fold enhancement in 2P uncaging sensitivity at 730 nm compared to the NI cage which validates the proof of concept. The energy transfer-based route thus holds major promises for 2P uncaging of biomolecules. We are currently extending it to the elaboration of modular synergic systems having larger 2P uncaging sensitivity. (1) P. Klan, T. Solomek, C. G. Bochet, A. Blanc, R. Givens, M. Rubina, V. Popik, A. Kostitov, J. Wirz. Chem. Rev., 2013, 113, (2) a) G. C. Ellis-Davis. ACS Chem. Neurosci., 2011, 2, ; b) G. Bort, T. Gallavardin, D. Ogden, P. I. Dalko. Angew. Chem. Int. Ed., 2013, 52, (3) S. Picard, E. Cueto-Diaz, E. Genin, G. Clermont, F. Acher, D. Ogden, M. Blanchard- Desce. Chem. Commun. 2013, 49,

10 Alexandre Guthertz SMB CO-4 Synthèse du fragment spiroimine de la gymnodimine et du 13-desmethyl spirolide C A. Guthertz, J. Labarre-Lainé, I. Periñan, V. Desvergnes, Y. Landais Université de Bordeaux, Institut des Sciences Moléculaires, UMR-CNRS 5255, 351, cours de la libération, Talence Cedex, FRANCE Les spirolides et les gymnodimines sont des phycotoxines à imine cyclique produites par des microalgues de type dinoflagellé (Alexandrium Ostenfeldii et Alexandrium peruvianum). Isolés pour la première fois au début des années 90 dans des extraits de fruits de mer, ils peuvent être transférés aux animaux marins et à l Homme via la chaîne alimentaire. Les problèmes sanitaires et économiques qui en découlent ont amené la communauté scientifique à s intéresser de plus près à ces toxines. Les spirolides, avérés toxiques par injection intrapéritoneale à des souris (IC 50 = 7-9 mg/kg), sont des antagonistes des récepteurs nicotinique de l acétylcholine. Mais ils se sont aussi révélés neuroprotecteurs à de plus faibles concentrations. En réduisant simultanément les taux d amyloide β et l hyperphosphorylation de la protéine Tau, les spirolides pourraient être étudiés comme traitement de la maladie d Alzheimer. Malheureusement la biodisponibilité de ces phycotoxines est trop faible pour envisager des études toxicologiques plus approfondies. Plusieurs groupes se sont intéressés à la synthèse de ces molécules, en 2009, la première synthèse totale de la gymnodimine a été décrite par l équipe de D. Romo. Mais pour les spirolides, à ce jour, aucune synthèse totale n a été publiée. Dans le cadre de la synthèse totale du 13-desmethyl spirolide C et de la gymnodimine A, membres les plus étudiés de ces familles, nous proposons une approche générale au fragment spiroimine du spirolide et de la gymnodimine à partir d une réaction de Diels-Alder asymétrique. Références (1) J. Labarre-Lainé et al., Chem. Eur. J., 2014, 20, (2) D. Romo et al., Angew. Chem. Int. Ed. 2009, 48,

11 Aleksandar Karajić NSYSA CO-5 Development of Electrode Architectures for Miniaturized Biofuel Cells A. Karajić a, S. Reculusa a,b, M. Heim a, S. Ravaine b, N. Mano b, A. Kuhn a a NSysA research group, Institute of Molecular Sciences, University of Bordeaux, CNRS and INP Bordeaux ENSCBP, 16 avenue Pey Berland, Pessac, France b Centre de Recherche Paul Pascal, CNRS and University of Bordeaux, Avenue Albert Schweitzer, Pessac, France Designing the architecture of miniaturized electrodes is one of the key-challenges in the field of the fabrication of implantable devices. Taking advantage of the high active surface area of macroporous gold and the cylindrical geometry [1], we developed a new strategy [2] for fabricating a microelectrochemical cell based on two coaxial and porous electrodes being independently addressable (Fig. 1). Figure 1. (a,b) SEM images of the two coaxial electrodes forming the miniaturized electrochemical cell; (c) Cyclic voltammograms in 0.5M H 2 SO 4 illustrating their electrical independence and thus the structural stability of the device. The ability to precisely control both electrodes thickness and their inter-distance combined with radial diffusion presents new promising opportunities for solving problems regarding the low current density and power output of most of the existing biofuel cells [3]. 1. M. Heim, S. Reculusa, S. Ravaine, A. Kuhn, Adv. Funct. Mater. 22 (2012) ; S. Reculusa, M. Heim, F. Gao, N. Mano, S. Ravaine, A. Kuhn, Adv. Funct. Mater., 21 (2011) «Method for manufacturing a miniaturized electrochemical cell» Patent EP , I. Willner, Y. M. Yan, B. Willner, R. Tel-Verer, Fuel Cells, 1 (2008)

12 Dieuwertje Schrijvers CYVI CO-6 Modeling the environmental benefits of recycling in Life Cycle Assessment D. L. Schrijvers, G. Sonnemann Building A12, 351 Cours de la Libération, Talence, France There is a growing concern about the environmental impact of products. Life Cycle Assessment (LCA) is a method that assesses the environmental impact of a product during its complete life cycle, which comprises the extraction of raw materials, the manufacturing, transport, use phase and the waste treatment of the product. The object of study in LCA is a functional unit, i.e. a quantification of the function that the product delivers, for example packaging material for 1 liter of liquid, or solvent to dissolve 1 kg of material. The environmental impact of a product can be decreased if the product is recycled. Recycling enables the product to be used in two or more life cycles, therefore it can fulfill multiple functions. However, how the environmental impact of the primary production and the recycling process is shared between those functions, is a topic of debate in LCA. This is illustrated by a case study where PVC waste from cables (the first life cycle) is recycled into PVC for garden hoses (the second life cycle). Do PVC cables have a low environmental impact because they are recyclable? Or do garden hoses have a low impact because PVC waste treatment is avoided and no primary PVC is used? Making both claims at the same time leads to double counting of the benefits of PVC recycling. Therefore, only the production of recycled PVC in the first life cycle or the consumption of recycled PVC in the second life cycle can lead to environmental benefits. Alternatively, the benefits of recycling can be shared by the PVC cables and the garden hoses, for example by 50% in the 50/50 method. The metals sector argues that all the recycled metal will be used, so only the production can lead to environmental benefits (1). Contrarily, there is often a lack of demand for recycled plastics, therefore an increased consumption could lead to environmental benefits. The European Commission proposes in the Product Environmental Footprint Guide that the 50/50 method should be applied in all material sectors, which could lead to unrealistic results for products containing metals. Therefore, we need a modeling method that can be applied by all product groups, without introducing bias. This method must be applicable to both the first and the second life cycle without double counting or omitting environmental impacts. We propose a new modeling method that considers the market price of the recycled material compared to the market price of the substituted primary material. A high market-price ratio favors the production of this material, while a low ratio stimulates its consumption. This method enables the comparison of materials from different sectors for the same function, e.g. aluminum and plastic packaging. This method needs to be applied on several case studies, to determine whether the market-price ratio is a representative factor for all product groups. Otherwise, typical ratios should be determined that indicate whether the production or the consumption of a recycled material leads to environmental benefits. This could contribute to more realistic sustainability claims regarding the recyclability or the recycled content of a product. (1) J. Atherton, Int J LCA, 2007, 12,

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15 Vasilica Badets NSYSA CA-1 Local generation of TiO 2 and rapid screening of photoelectrochemical activity by SECM V. Badets, a G. Loget, b P. Garrigue, a N. Sojic, a D. Zigah a a Univ. Bordeaux, ISM, UMR 5255, F Talence, France b Univ. Rennes 1, ISCR, UMR 6226, Rennes, France Surface patterning represents a new tool for a large variety of analytical applications and electronics development. Titanium dioxide is one of the most investigated compounds in materials science due to its unique properties that enable its use in a wide variety of applications such as solar cells and photocatalysis [1]. Different nanoparticulated forms of TiO 2 are used to achieve maximum overall efficiency but self-organized nanotubes are considered as the most spectacular and surprising 1D structures [2]. In this work, we present the localized growth of TiO 2 confined to a micro-sized region and the use of a combined optical fiber-secm for the screening of the photoelectrochemical properties for water splitting. The localized anodization of a Ti substrate was performed using an original tool composed of a capillary combined with a gold microelectrode (figure 1A). A local spot containing TiO 2 nanotubes was hence obtained. On the same substrate, different spots were obtained by varying the anodization potential (figure 1B). A high-throughput screening of the photoelectrochemical properties of these spots was achieved by locally illuminating the surface with UV light provided by a movable optical fiber. The oxidation current associated with water splitting was recorded on the entire substrate and hence the photoelectrochemical activity of each spot could be imaged. A direct correlation was obtained with the morphology of each spot obtained from SEM analysis. A) B) Figure 1. A) Combined capillary-gold microelectrode tool used to locally anodize a Ti plate. B) SECM-optical image of TiO 2 spots grown using a combined capillary-microelectrode tool on a Ti substrate with different anodization potentials. (1) G. Loget, S. So, R. Hahn, P. Schmuki, J. Mater. Chem. A (2) D. Zigah, J. Lopez, A. J. Bard, Phys. Chem. Chem. Phys

16 Vasilica Badets NSYSA CA-2 SECM Writing and Reading with an Original Dual Microelectrode V. Badets, a D. Quinton, a O. Fontaine, b D. Zigah a a Univ. Bordeaux, ISM, UMR 5255, F Talence, France b Univ. Montpellier 2, UMR 5253, CC1701, Montpellier France kwamidodzi.zigah@u-bordeaux1.fr Surface patterning with molecules is becoming a reliable tool for a large range of applications such as analytical science or molecular electronic. The development of Scanning Electrochemical Microscopy (SECM) allows to locally modify surfaces using electrochemical reactions generated by a microelectrode. Click chemistry coupled with SECM is a very easy way to locally modify surfaces with a large variety of molecules 1. In this work we present an original surface modification using a unique dual coppergold microelectrode. The copper electrode is used to write on the surface meanwhile the gold electrode is used to read the modification. The entire surface of glassy carbon was firstly modified by electrografting of an aryldiazonium salt containing an azide moiety. Secondly, the local azide-alkyne cycloaddition using a ferrocene alkyne was performed by a Cu(I) ion generated at the copper electrode. This click reaction was located in a small area under the copper part of the microelectrode positioned closely to the surface. This writing reaction was followed by a reading procedure in which the ferrocene immobilized on the surface was observed by SECM in feedback mode. For this, the gold part of the dual microelectrode was used. This procedure proves the versatility of systems that could be developed using the newly presented click coupled SECM dual microelectrode setup. Fig. 1. A) Generation of Cu(I) by oxidation of Cu microelectrode. B) Feedback mode to observe the immobilized ferrocene using the Au microelectrode. C) Optical image of the dual microelectrode. D) SECM image of the immobilized ferrocene in feedback mode. (1) S. Lhenry, Y.R. Leroux, C. Orain, F. Conan, N. Cosquer, N.L. Poul, O. Reinaud, Y.L. Mest, P. Hapiot, Langmuir

17 Flavie Bondu GSM CA-3 Hyper-Rayleigh Scattering Characterization of Electro-(Photo) Switchable Benzazolooxazolidine Derivatives F. Bondu, a G. Szaloki, b L. Sanguinet, b J.-L. Pozzo, a T. Buffeteau, a V. Rodriguez a a Université de Bordeaux, Institut des Sciences Moléculaires (ISM), UMR 5255 CNRS, 351 Cours de la Libération, Talence CEDEX, France b Université d Angers, MOLTECH-Anjou UMR CNRS Bd Lavoisier, Angers CEDEX, France In recent years, the increasing need of information transport and storage leads to the design and synthesis of molecular multistate devices. In that respect, Self-Assembled Monolayers (SAMs) of multi-switchable molecules are of particular interest. Indolino[2,1-b]oxazolidine derivatives have been studied over the last decade.[1,2] They exhibit a reversible transformation, triggered by ph-change or light irradiation, between a closed and an open ring form. This transformation strongly modifies the electronic distribution inducing a high nonlinear optical (NLO) contrast between these two forms. Thus indolino[2,1-b]oxazolidine derivatives appear as highly attractive candidates for NLO applications. In this work, promising electro-(photo)switchable indolino[2,1-b]oxazolidine derivatives were synthesized in order to be used for SAMs applications. The ring opening can also be obtained from an electrochemical oxidation and can be reversibly closed by an electrochemical reduction. We report the characterization of this molecule in solution using Hyper-Rayleigh Scattering which is a powerful method to monitor and determine the second order NLO response of the moieties. We show that both electro and photo opened forms exhibit the same visible absorption and NLO features. +1V -0.5V Electro-modulated ring opening and closing of iondolino[2,1-b]oxazolidine derivative (potentials are expressed versus platinum pseudo-reference electrode) (1) L. Sanguinet, J.-L. Pozzo, V. Rodriguez, F. Adamietz, F. Castet, L. Ducasse, B. Champagne, J. Phys. Chem. B, 2005, 109, (2) F. Castet, V. Rodriguez, J.-L. Pozzo, L. Ducasse, A. Plaquet, B. Champagne, Acc. Chem. Res., 2013, 46,

18 Sébastien Bonhommeau GSM CA-4 Surface-enhanced Raman spectroscopic study of metal-semiconductor and metal-dielectric interfaces for organic thin-film transistor applications S. Bonhommeau, a S. Sirotkin, a S. Desplanche, a A. Pereira, b C. Constantinescu, c D. Talaga, a C. Videlot-Ackermann, d A.P. Alloncle c et V. Rodriguez a a Université de Bordeaux/CNRS, ISM, UMR 5255, F Talence, France b Université Claude Bernard Lyon 1/CNRS, ILM, UMR 5306, F Villeurbanne, France c Université Aix-Marseille/CNRS, LP3, UMR 7341, F Marseille, France d Université Aix-Marseille/CNRS, CINaM, UMR 7325, F Marseille, France In order to reveal the origin of low electrical performances in organic thin-film transistors (OTFTs) fabricated by means of laser-induced forward transfer, 1 surface-enhanced Raman scattering (SERS) studies are achieved at gold/semiconductor (pentacene) and gold/dielectric (poly(4-vinylphenol)) interfaces. 2 Regarding the dielectric, low-wavenumber spectral features undetectable in normal Raman spectroscopy are discerned. In pentacene, a prominent marker band at 1598 cm -1 reflects the formation of a disordered phase, strongly contrasting with the thin-film phase 3 observed in regions devoid of gold. SERS spectra also suggest that the ordering of the pentacene phase depends on the thickness of gold electrodes grown by pulsed laser deposition. (1) L. Rapp, A.K. Diallo, A.P. Alloncle, C. Videlot-Ackermann, F. Fages, P. Delaporte. Applied Physics Letters, 2009, 95, (2) S. Sirotkin, S. Desplanche, A. Pereira, C. Constantinescu, D. Talaga, C. Videlot- Ackermann, A.P. Alloncle, V. Rodriguez, S. Bonhommeau. In preparation (3) H.-L. Cheng, Y.-S. Mai, W.-Y. Chou, L.-R. Chang, X.-W. Liang. Advanced Functional Materials, 2007, 17,

19 Thomas Cornilleau SMB CA-5 En route vers la carbonylation supportée pour la synthèse rapide, pratique et automatisable de biotraceurs Thomas Cornilleau, 1 Hélène Audrain, 2 Aude Guillemet, 1 Philippe Hermange* 1 and Eric Fouquet* 1 1 Institut des Sciences Moléculaires, Groupe Synthèse de Molécule Bioactive, LabEx TRAIL, 351 cours de la libération, F Talence (France) 2 Department of Nuclear Medicine and PET Center, Aarhus University Hospital, Nørrebrogade 44, DK-8000 Aarhus (Danemark) La recherche médicale et le diagnostic requièrent des traceurs biologiques facilement accessibles avec une très haute affinité pour les processus biologiques ciblés. De part la grande diversité et complexité de ces biomolécules, il est crucial de développer un marquage régiosélectif dans des conditions douces et en dernière étape de synthèse. [1] Une stratégie envisageable est le couplage d une biomolécule avec une plateforme synthétique spécifique du marqueur. Injection au patient Radiomarquage-Clivage Image TEP L utilisation du monoxyde de carbone est pertinente car elle permet un vaste choix d isotopes: 12 C, 13 C, ou encore le radio-isotope 11 C (T 1/2 = 20,4 min). Celui-ci présente un intérêt particulier pour la Tomographie par Emission de Positron (TEP), une technique d imagerie nucléaire en pleine croissance. [2],[3] La stratégie envisagée est basée sur la préparation de complexes Pd-benzylalcoolates [4] ancrés sur un support solide. Ces complexes seront ensuite fonctionnalisés par un ligand spécifique de la cible biologique choisie. L étape de carbonylation permettra le marquage ainsi que le clivage sélectif du radiotraceur de son support en une seule étape! Références [1] F. Lodi, C. Malizia, P. Castellucci, G. Cicoria, S. Boschi, Nucl. Med. Biol. 2012, 39, 447. [2] K. Dahl, M. Schou, N. Amini, C. Halldin, Eur. J. Org. Chem. 2013, 2013, [3] Cornilleau, T.; Audrain, H.; Guillemet, A.; Hermange, P.; Fouquet, E. Org. Lett. 2015, 17, 354. [4] Andersen, T. L. ; Friis, S. D.; Audrain, H.; Nordeman, P.; Antoni, G.; Skrydstrup, T. J. Am. Chem. Soc. 2015, 137, 1548.

20 Morgan Floch C2M CA-6 Identification of six new odor active alkylpyrazines in Oak wood M. Floch a,b, S. Shinkaruk-Poix b,c, B. Bennetau b, P. Darriet a, A. Pons a,d a Université Bordeaux, ISVV, EA 4577, F Villenave d Ornon, France b Université Bordeaux, CNRS, UMR 5255 ISM, F Talence, France c Bordeaux Sciences Agro, F Gradignan, France d Seguin Moreau France, Z.I. Merpins, B.P. 94, F Cognac, France Oak (Quercus sp.) is currently the only wood used in making barrels for fermenting and aging quality wines. The fundamental aspect of aging wines in oak concerns the aromatic compounds extracted from the wood. When these compounds marry perfectly with a wine s intrinsic aromas, they make a significant contribution to the richness and complexity of the bouquet, as well as improving the flavor. Volatile extractive compounds from oak wood are responsible for important pleasant olfactory notes, such as coconut, wood, vanilla, caramel, and spice. Unfortunately, not all of them are pleasant. Indeed, for example, sawdust or musty are well known off flavours. Recently, a new off flavour reminiscent of rancid was more frequently found in certain oak wood. Odoriferous zones (OZs) with strong odor reminiscence of the contaminated oak wood flavors were characterized by GC-O. Six odoriferous zones were identified. Using several techniques such as GC-O-MS, GC-GC-O-MS and GC-O-NPD six compounds containing nitrogen atoms were associated with these OZs. Regarded mass spectrum interpretation and literature data, their chemical structures were assigned a priori to several disubstituted pyrazines with isopropyl, isobutyl and sec-butyl side chains. The identification of new alkylpyrazines was confirmed by comparison with synthetic reference compounds. For this purpose the six pyrazines were prepared via a three step - one pot reaction by reducing a mixture of activated amino acids (Val, Leu, iso-leu) with DIBAL-H at low temperature Relative Abundance ZO1 ZO4a ZO2 ZO3 ZO4b ZO4c Time (min) After HPLC-UV purification, their structures and purity were confirmed by several analytical methods (NMR, HR-MS, IR). The use of synthetic alkylpyrazines allowed the reliable identification and characterization of six OZs and validated their first identification in oak wood.

21 Eugenio Gianessi NSYSA CA-7 Hierarchical macro-mesoporous gold electrodes for the efficient electrocatalytic reduction of oxygen. Eugenio Gianessi a, Nicolas Mano b, Serge Ravaine b and Alexander Kuhn a a ISM, Université Bordeaux, Site ENSCBP, 16 avenue Pey Berland, Pessac, France b Centre de Recherche Paul Pascal, 115, avenue du Dr Schweitzer, Pessac, France The oxygen reduction reaction (ORR) is central to many energy related processes occurring for example in fuel cells and batteries. A variety of electrode materials has been proposed in the past as electrocatalysts for this reaction. Gold is usually not so well known for being active with respect to ORR. However when present in a nanostructured form quite impressive catalytic activities have been reported [1]. Here we present a new method for elaborating gold electrodes with a hierarchical porous structure and study the catalytic effect that this type of electrodes can have on the reduction of oxygen. The electrode structure is obtained by creating first a macroporous gold electrode with the Langmuir-Blodgett technique [2,3], which then is anodized in the presence of oxalic acid [4] to obtain generate an additional mesoporosity [5]. This results in a dramatic increase of the active surface area. The synergy of transportenhancing macropores and surface-enhancing mesopores leads to electrodes with significantly improved catalytic activities. Comparison of the active surface area of a same electrode before and after anodization (left) and comparison of the oxygen reduction current of a flat, macroporous and macromesoporous electrode having the same geometrical area (right). [1] El-Deab et al., Electrochem.Comm. 2002, 4, 288 [2] Reculusa et al., Adv.Funct.Mater. 2011, 21, 691 [3] Heim et al., Adv.Funct.Mater. 2012, 22,538 [4] Nishio et al., Angew.Chem.Int.Ed., 2011, 50, 1603 [5] Heim et al., Electroanal. 2013, 25, 888

22 Simon Grélaud SMB CA-8 Diastereoselective Access to 2,3,5-substituted Tetrahydrofurans : Application to Natural Product Synthesis S. Grélaud et Y. Landais Université de Bordeaux, Institut des Sciences Moléculaires, UMR-CNRS 5255, 351, cours de la libération, Talence Cedex, France The 2,3,5-substituted tetrahydrofuran skeleton is present in many natural products of biological interest. 1 This fragment still constitutes a synthetic challenge, including the control of the stereochemistry of the three non-contiguous stereocenters. We describe here a diastereoselective access to the 2,3,5-substituted tetrahydrofuran skeleton, based on the addition of an acyl radical onto electron-poor olefins, using phenylseleno esters as the acyl precursor. Free-radical acyl addition to Baylis-Hillman adducts, followed by a reductive cyclization thus provides an access to the tetrahydrofuran core with high level of stereocontrol. R 1 O SePh EtO O OTBDPS R TTMSH (1,5 eq.) DTBHN (0.1 eq.) Benzene, 45 C, 12-24h O EtO R 1 O OTBDPS R up to 91% yield up to 19:1 d.r. BF 3.Et 2 O (2 eq.) TTMSH (4 eq.) MeCN, RT, 12h R 1 O O OEt R up to 100% yield up to 19:1 d.r. 1 a) T. Seki, M. Satake, L. Mackenzie, H. F. Kaspar, T. Yasumoto, Tetrahedron Lett. 1995, 36, ; b) A. Torre, Y. Y. Lee, C. Oger, P. T. Sangild, T. Durand, J. C.- Y. Lee, J.-M. Galano, Angew. Chem. Int. Ed. 2014, 53, ; c) T. Iwai, T. Kubota, J. Kobayashi, J. Nat. Prod. 2014, 77,

23 Hubert Céline NSYSA CA-9 Engineering new patchy nanoparticles for directed assembly C. Hubert, a,b C. Chomette, c P.E. Rouet, a A. Madeira, c M. Sun, c S. Mornet, c M. Treguer Delapierre, c E. Duguet, c S. Ravaine, c A. Perro a a ISM Univ. Bordeaux, Pessac, France b CRPP-CNRS Univ. Bordeaux, Pessac, France c ICMCB-CNRS Univ. Bordeaux, Pessac, France In this communication, we report on a new route to synthesize patchy nanoparticles with a controlled number of patches or dimples as well as on their potential use as building blocks for the elaboration of new supracolloids with unusual morphology and optical properties. The so-patchy particles were derived from colloidal molecules [1] made of a central silica core surrounded by a precise number n of polystyrene satellite nodules [2,3]. We succeeded in promoting the growth of the silica core of these colloidal molecules. While growing, the silica surface conforms to the shape of the PS nodules. After functionalization of the inter-nodule surface area and dissolution of the polystyrene nodules, homogeneous batches of silica particles with n well-located patches at their surface can be produced in large quantities [4,5]. The patchy character of the silica particles was evidenced by TEM characterization (see Figure) as well as regioselective functionalization. These patchy particles offer the unique capability of creating new nano-objects suitable for many applications such as sensing, metamaterials, photonics, etc. For example, they can be used to elaborate nanocages of noble metal with a controlled number of holes as well as complex supracolloids by assembly with other nanoparticles. Figure. TEM image of silica particles with four (left) and twelve (right) patches [4]. [1] E. Duguet, A. Désert, A. Perro and S. Ravaine, Chem. Soc. Rev. 2011, 40, 941. [2] A. Perro, E. Duguet, O. Lambert, J. C. Taveau, E. Bourgeat-Lami and S. Ravaine, Angew. Chem., Int. Ed. 2009, 48, 361. [3] A. Désert, I. Chaduc, S. Fouilloux, J.C. Taveau, O. Lambert, M. Lansalot, E. Bourgeat-Lami, A. Thill, O. Spalla, S. Ravaine and E. Duguet, Polym. Chem. 2012, 3, 1130 [4] A. Désert, C. Hubert, Z. Fu, L. Moulet, J. Majimel, P. Barboteau, A. Thill, M. Lansalot, E. Bourgeat-Lami, E. Duguet and S. Ravaine, Angew. Chem. Int. Ed. 2013, 52, [5] C. Hubert, C. Chomette, A. Désert, M. Sun, S. Mornet, M. Treguer Delapierre, E.Duguet, S. Ravaine, A. Perro, Faraday Discussion, 2015, DOI: /C4FD00241E.

24 Petra Ivaskovic PHOENICS CA-10 Synthesis of plasmonic nanostructures for guiding light Petra Ivaskovic 1,2, Jean-Baptiste Verlhac 2, Renaud Vallée 1, Mireille Blanchard-Desce 2, Serge Ravaine 1 1 Centre de Recherche Paul Pascal (CNRS), University of Bordeaux, France 2 Institut des Sciences Moléculaires (UMR5255 CNRS), University of Bordeaux, France Metal nanostructures have received a great attention in recent years due to their unique optoelectronic properties which are geometry-dependent and can thus be easily tuned. We are fabricating new types of plasmonic architectures that can be used to investigate the possibility of transport control and routing of the light, establishing an approach to nanoscale plasmonic switching and finally aiming at nanoscale light manipulation. This would lead to many possible applications ranging from nanoelectronics, information processing and communication. In that context, we are designing different types of nanostructures i) Y-shaped plasmonic nanostructure that consists of three gold nanorods assembled via an organic tripodal molecule and ii) V-shaped gold nanoframes. In such systems, after the excitation of one tip of the structure, the resulting plasmon is expected to propagate through a desired direction and meant to be detected via the emission of a fluorescent dye attached to their tips (Fig. 1). Fig. 1: Hybrid plasmonic nanostructures a) Y- shaped architecture b) V-shaped architecture c) complete emission in one branch of the nanostructure Gold nanorods are used as building blocks for Y-shaped nanostructure and linked in a controlled Y-shape geometry via the use of a dedicated organic assembler. Organic 3-branched molecules are being synthetized in order to serve as assembling modules between three gold nanorods to yield nanopolaritonic structures. The goal is i) to design and prepare tripodal concave molecules having rigid arms and peripheral moieties showing good affinity for gold, ii) to graft the gold nanorods onto the organic assembler as well to iii) graft fluorescent dyes on the nanorods tips. Hollow gold V-shaped nanostructures were obtained by a galvanic replacement reaction between silver nanoprisms and gold, which was deposited on the edges of the silver templates. In conclusion, we are designing and fabricating nanostructures aiming to direct the polariton flow toward the desired direction, forming an optical switch and providing access to nanoscale light manipulation. ACKNOWLEDGMENTS We acknowledge financial support from Cluster LAPHIA, IDEX Bordeaux project (InPhotArch).

25 Aileen Justies NSYSA CA-11 Controlled redox-mediated drug release from diblock copolymer micelles A. Justies, a A. Lu, b P. Barthélémy, c A. Kuhn, a S. Lecommandoux, b V. Ravaine a a Université de Bordeaux,UMR 5255 Groupe NsysA, ISM ENSCBP, Pessac Cedex, France b Université de Bordeaux, Bordeaux INP, LCPO, UMR 5629, Pessac, France c Université de Bordeaux, ChemBioMed, INSERM U Bordeaux Cedex, France Materials for loading and controlled release on-demand, with the ability to return into a steady state, are of tremendous interest for drug administration. The aim of this work is to design materials based on the self-assembly of biocompatible polymers and to tailor their loading/release properties by redox triggers. Known redoxresponsive materials are based on e.g. disulfide bonds or ferrocene inclusion complexes. [1] The introduction of biocompatible, hydrophobic, redox-responsive moieties into a hydrophilic biocompatible polypeptide backbone would lead to a new generation of redox-responsive materials. [2] As the polymer scaffold a poly(ethylene glycol)-block-poly(l-glutamate) PEG-b- PGA diblock copolymer was used. [3] L-Tryptophan (Trp) was coupled onto the polymer via the acidic groups of PGA in order to introduce redox-responsive properties, thus obtaining PEG-b-PLG Trp. Such a modification is of particular interest as, in addition to its redoxresponse, its change in redox state influences its hydrophobic nature, which alters the selfassembly behavior of the polymer. [4] The resulting PEG-b-PLG Trp copolymers form welldefined micelles, which are able to encapsulate hydrophobic molecules. The release of these molecules can be achieved by electrochemical or chemical oxidation. These triggers change the loading ability of the micelle, by decreasing the hydrophobicity of the tryptophan. The resulting micelle destabilization triggers the drug release. [1] a L. Zhang, W. Liu, L. Lin, D. Chen, M. H. Stenzel, Biomacromolecules 2008, 9, ; b Y. Ma, W.-F. Dong, M. A. Hempenius, H. Mohwald, G. Julius Vancso, Nature Materials 2006, 5, [2] A. Carlsen, S. Lecommandoux, Current Opinion in Colloid & Interface Science 2009, 14, [3] W. Agut, A. Brûlet, D. Taton, S. Lecommandoux, Langmuir 2007, 23, [4] N. T. Nguyen, M. Z. Wrona, G. Dryhurst, Journal of Electroanalytical Chemistry and Interfacial Electrochemistry 1986, 199,

26 Pauline Lefrançois NSYSA CA-12 Electrochemistry Coupled with Confocal Microscopy to Detect Fluorogenic Species Formed by Enzymatic Reactions in Biomimetic Vesicles P. Lefrançois, V. S. Vajrala, B. Goudeau, L. Bouffier, S. Arbault University of BORDEAUX, Institute of Molecular Sciences, CNRS UMR 5255, NSysA Group, ENSCBP, Pessac, FRANCE The project aims to study enzymatic reactions in cell-sized confined vesicles ( µm diameter), made of a unilamellar phospholipidic membrane (GUV) or diblock-polymers (polymersome). Electroformation of phospholipidic GUVs in physiological conditions (PBS, ph 7.4, 300 mosm) is achieved, allowing a further characterization of enzymatic activities within such a cell-mimicking compartment. Once the vesicles are formed, their internal media have to be modified on purpose, herein by microinjection of the reactants into the vesicle. We currently study a biochemical system that involves two enzymatic reactions: glucose oxidase transforms glucose into gluconolactone and hydrogen peroxide, which is detected by the oxidative conversion of Amplex Red (AR) into resorufin by peroxidase. Resorufin is a fluorescent product which allows to follow easily the progress of the reaction by confocal microscopy. The other challenge consists in detecting the species formed by these enzymatic reactions by electrochemistry. The approach consists in detecting the diffusion of the reaction products through the lipid membrane, using an ultramicroelectrode placed in the vicinity of the membrane. A spectroelectrochemical study of Amplex Red and resorufin in solution was achieved, by following these reactions under redox control with a confocal microscope. Amplex Red and resorufin were both electroactive; interestingly, non-fluorescent AR can be reduced electrochemically to form resorufin in absence of enzymatic conversion. Combining fluorescence and electrochemical methods will allow us to monitor and quantify enzymatic reactions within a single biomimetic reactor. (1) T. Pott, Chemistry and Physics of Lipids Contents, 154 (2008) (2) N. Gajovic Eichelmann, Electroanalysis, 17 (2005)

27 Haidong Li NSYSA CA-13 Electrochemistry and electrogenerated chemiluminescence of cationic triangulene dyes: crucial influence of the core heteroatoms C. Adam a, A. Wallabregue b, H. Li a, J. Gouin b, R. Vanel b, S. Grass b, J. Bosson b, L. Bouffier a, J. Lacour b, N. Sojic a a University of Bordeaux, ISM, UMR CNRS 5255, 16, Avenue Pey Berland, Pessac, France b University of Geneva, Department of Chemistry. 30, Quai Ernest Ansermet, 1211 Geneva 4, Switzerland Cationic triangulene dyes with planar fully conjugated structures are highly stable carbocations which exhibit interesting electrochemical and luminescent properties. 1 Herein, a series of triangulene dyes were selected to investigate the infulences on electrochamical behavior and electrogenerated chemiluminescence (ECL) by either replacing the heteroatoms in the core progressively or changing the pending chemical groups. ECL from these luminophores was produced by a reductive-oxidation pathway. 2 In this case, benzoyl peroxide (BPO) co-reactant is reduced simultaneously with the luminophore at the surface of the electrode. After dissociation, BPO produces a strong oxidant that will oxidize the luminophore to generate the excited state which can emit light. The ECL efficiency of the luminophores was calculated by comparing to Ru(bpy) 3 2+ /BPO system. The dramatical variation in ECL intensity with the molecular structure changing was observed among these luminophores. The oxygen heteroatom in the core structure can strongly affect the ECL capability, triazatriangulenium (TATA, no oxygen heteroatom) exhibits the most strong ECL while trioxatriangulenium (TOTA, 3 oxygen heteroatoms) gives very weak ECL emission. 3 A comparison between the ECL and fluorescence behavior is drawn as well as a thermodynamic rationalization of the ECL efficiency. BF 4 BF 4 BF 4 BF 4 O O R 1 N O R 1 N NR 2 R 1 N NR 2 O O O N R 3 TOTA TATA ADOTA Pr R 1 = n Pr Ph R 1 = n Pr DCP R 1 = DCP DAOTA Pr R 1 = R 2 = n Pr Ph R 1 = Ph, R 2 = Me DCP R 1 = DCP, R 2 = n Pr R 1 = R 2 = R 3 = n Pr (1) J. Bosson, J. Gouin, J. Lacour. Chem. Soc. Rev. 2014, 43, (2) A. J. Bard, Electrogenerated Chemiluminescence, M. Dekker, NewYork, (3) C. Adam, A. Wallabregue, H. Li, J. Gouin, R. Vanel, S. Grass, J. Bosson, L. Bouffier, J. Lacour, N. Sojic. submitted.

28 Lozan Ecaterina C2M CA-14 Novel derivatization reagents to enhance ionization efficiency of 17-β-Estradiol in LC-MS/MS Ecaterina Lozan a,b*, Corinne Buré b, Chloé Papin a, Catherine Bennetau-Pelissero c, Jean-Marie Schmitter b, Svitlana Shinkaruk b,c a ISM, Université de Bordeaux, France; b CBMN, Université de Bordeaux, France ; c Neurocentre Magendie, Université de Bordeaux, France 17-β-Estradiol (βe2) is a key steroid hormone implicated in reproduction. Moreover, βe2 has an important role in the functioning of the brain and of the nervous system. This study aims at the design of a suitable analytical method for the identification and quantification of βe2 present at low concentration in the mouse brain (around 1 fmol/mg) and plasma (around 0.01 fmol/µl). Liquid chromatography coupled to tandem mass spectrometry (LC-MS/MS) with electrospray ionization (ESI) with Multiple Reaction Monitoring (MRM) is one of the most prominent techniques due to its high specificity and sensibility. The ionization of βe2 is not very efficient in conventional negative or positive ESI mode, resulting in low abundance of [M-H] or [M+H] + molecular ions. Chemical derivatization is frequently used to enhance the MS ionization efficiency through the introduction of easily ionizable groups. Nitrogen-containing aromatic sulfonyl chlorides, like Dansyl chloride originally used for phenol and amine fluorescence detection, were borrowed for this purpose. 1-3 Already described in literature, sulfonyl βe2 derivatives either did not present analyte-specific fragment ions or were not enough stable for routine application. These data prompted us to investigate additional commercially available sulfonyl chlorides and isocyanates as potential derivatization reagents. Six new βe2 derivatives were synthesized by procedures suitable for biological sample treatment and then characterized by NMR and HR-MS. Next agents were used: 8-Quinoline-sulfonyl chloride (Q8S-Cl), p- Toluenesulfonyl isocyanate (p-tsi), 4-Nitrophenyl isocyanate, Phenyl isocyanate, 4- Dimethylaminophenyl isocyanate (DMAPI), and 4-Fluorophenyl isocyanate. The goal was to identify ones that produced stable derivatives with analyte-specific fragment ions in MS/MS. In positive ESI-MS mode, Q8S-Cl and DMAPI reagents effectively enhanced the ionization efficiency of βe2. In negative ESI-MS mode, the best ionization was obtained for ptsi-βe2 derivative. Only the ESI-MS/MS spectrum of Q8S-βE2 provided specific fragment ions and was therefore chosen for the development of a quantitative method. LC-MS/MS analyses in MRM mode were performed on a 5500 QTRAP (AB Sciex) instrument coupled to a LC system (Ultimate 3000, Dionex). Very low limits of detection and quantification have been found (0.025 fmol/µl and 0.1 fmol/µl, respectively). The method has been validated to be specific and sensitive, with a good linearity and repeatability. It is currently used for the assay of βe2 in different brain areas. Keywords: Estradiol, derivatization, liquid chromatography, mass spectrometry 1. Anari M.R. et al. Anal. Chem. 2002, 74, Xu L. et al. J. Chromatography B, 2007, 855, Xu L. et al., Anal Biochem, 2008, 375, 105.

29 Siliu Lyu C2M CA-15 Organometallic Ru-Diacetylide Complexes as New Photosensitizers for p-type Dye-Sensitized Solar Cells Siliu Lyu, a Céline Olivier, a Thierry Toupance, a Yoann Faré, b Fabrice Odobel b a Institut des Sciences Moléculaires (ISM), CNRS UMR 5255, Université de Bordeaux, 351 cours de la Libération, Talence, France. b Chimie et Interdisciplinarité, Synthèse, Analyse, Modélisation (CEISAM), CNRS UMR 6230, Faculté des Sciences et des Techniques de Nantes, 2, rue de la Houssinière Nantes, France. Dye-sensitized solar cells (DSSCs) have attracted considerable attention in recent years as they offer the possibility of low-cost production of photovoltaic energy. [1] In contrast with conventional DSSCs, that include a photosensitized n-type semiconductor (i. e. TiO 2 ), dye-sensitized photocathodic solar cells (p-dssc) operate in an inverse mode with the transfer of a hole from a photoexcited dye to the valence band of a p-type semiconductor such as NiO. [2-3] Ultimately both types of electrodes (TiO 2 -based photoanodes and NiO-based photocathodes) can be associated in the same device, affording so-called tandem cells where the two electrodes are photoactive. In this context, we have recently reported the study of original Ru-diacetylide pushpull complexes as new type of organometallic dyes for n-dsscs. [4] The synthesis of these organometallic chromophores showing a D-π-[Ru]-π-A structure was successfully achieved and when grafted on TiO 2 electrodes, the new dyes provided conversion efficiencies above 7% and showed broad IPCE profiles. Based on this study, we have now designed two new p-type organometallic chromophores for the preparation of NiO-photocathodes. Here, we will describe the synthesis of the new complexes, the study of their opto-electronic properties and their efficiency in p- type DSSCs. [1] A. Hagfeldt, G. Boschloo, L. Sun, L. Kloo and H. Pettersson, Chem. Rev., 2010, 110, [2] M. Weidelener, A. Mishra, A. Nattestad, S. Powar, A. J. Mozer, E. Mena-Osteritz, Y.- B. Cheng, U. Bach, P. Bäuerle, J. Mater. Chem., 2012, 22, [3] F. Odobel, Y. Pellegrin, J. Phys. Chem. Lett., 2013, 4, [4] S. De Sousa, L. Ducasse, B. Kauffmann, T. Toupance, C. Olivier, Chem. Eur. J., 2014, 20, 7017.

30 Jennifer Noble GSM CA-16 Etude des complexes coronène / eau par spectroscopie IRTF en matrice cryogénique J. Noble a, A. Moudens b, C. Aupetit a et J. Mascetti a a ISM, UMR5255, Université de Bordeaux, Talence cedex, France b LERMA, UMR8112, Université de Cergy-Pontoise, Cergy-Pontoise cedex, France Les PAH (polycycles aromatiques hydrocarbonés) sont des macromolécules organiques présentant un intérêt astrophysique depuis la découverte des bandes d émission AIB (Aromatic Interstellar Bands) observées entre 3 et 15 µm, et attribuées aux modes de vibration de PAH, qui, après absorption du rayonnement UV des étoiles, émettent dans l infrarouge (IR). Toutefois, aucune molécule PAH spécifique n a été identifiée et de nombreuses espèces (PAH neutres, ionisés, hydrogénés, substitués, complexés) sont étudiées et proposées. D autre part, au sein des nuages moléculaires du milieu interstellaire, les espèces gazeuses se condensent sur les grains de poussière et de glace où elles évoluent par des processus thermiques et photochimiques pour former des molécules complexes. Les spectroscopies IRTF et UV-visible, associées à la technique des matrices cryogéniques, sont des outils précieux pour étudier la composition de ces glaces et ont permis d identifier des molécules et de comprendre leur formation. Nous avons ainsi étudié la photo-réactivité de PAH piégés dans des glaces d eau amorphes et mis en évidence la formation de quinones, de diols et de cétones par irradiation UV-visible du coronène (Figure) et du pyrène (1, 2). Afin d identifier les espèces intermédiaires formées au cours de ces réactions, nous étudions par spectroscopie IRTF la formation de complexes coronène(h 2 O) n, (n=1 à 6) dans des matrices cryogéniques d argon et leur photo-réactivité sous irradiation UV. Les spectres expérimentaux sont comparés aux spectres théoriques obtenus par des méthodes SCC-DFTB pour les complexes PAH(H 2 O) n (n=1,2) (3) et par des méthodes combinées orbitale/champ de force SCC-DFTB/FF prenant en compte l influence de l environnement matriciel pour les agrégats d eau (4). Références (1) Z. Guennoun, C. Aupetit, J. Mascetti PCCP 2011, 13, (2) Z. Guennoun, C. Aupetit, J. Mascetti J. Phys. Chem. A 2011, 115, (3) A. Simon, M. Rapacioli, J. Mascetti, F. Spiegelman PCCP 2012, 14, (4) A. Simon, C. Iftner, J. Mascetti, F. Spiegelman J. Phys. Chem. A 2015, 119, Ces recherches sont soutenues par le GDR EMIE et par l ANR (ANR-13-BS )